You're trying to crash the monthly payment, I get that, but get a lower rate or price and take down some principal. 

The crash in 2008 is also very predictable as everyone already waiting for who collapse since 2006.So in 2021 I did a few flips and sell it asap to time the Fed interest rate hikes, the timing is just perfect.

When a market crashes there is alway a point you can see when it crosses the  moving average line.  

What if the market crashes and my tenants rent decreases significantly from section 8? 

The crash coarse would be to read:- BRRRR by @David Greene- Long Distance Real Estate Investing by @David Greene- The Book on Estimating Rehab Costs by @J Scott- How to Win Friends and Influence People by Dale Carnegie (Important for that Networking Piece) - What Every Real Estate Investor Needs to Know about Cash Flow ... by Frank Gallinelli (To bolster your knowledge of running the numbers) If you want to go a little deeper, I love the CPA advice on BRRRR from @Brandon Hall.Listen to Podcast 327.

So I think you need to expand on your questions to include such things as: what are you doing to avoid the mistakes you and others made during the last crash?

You don’t need a crash to buy good deals you just need to understand how to buy or make good deals.

Market is crashing/market has not hit problem (I was hearing this until 2014), market has been climbing too long and is sure to crash soon, prices too high, negative initial cash flow, LL unfriendly, political uncertainty, family/work uncertainty, economy uncertainty, too busy (my usual limiter), cannot find a good investment properties (my second most used), etc. 

Best of luck with the Bob Okenwa free crash course.

Or should just waiting for market to possibly crash again would be best bet?